Assassins are nerds
Lenny's words rang true in Agent 'X' head.
And then he could not help but play back what he had seen lenny do with relation to the knowledge he knew.
Even though he had accused lenny earlier on, of abandoning things that he knew from his first world, this was obviously not the case.
Firstly, liquid nitrogen is practically an unholy place. It was the extreme of cold just like how liquid fire, 'lava' was the extremity of fire.
This meant that liquid nitrogen was every bit as dangerous as lava.
However, its capabilities unlike fire was not in the consumption, but rather, petrification of the body.
but that was on the condition that a body was was placed into it. but it gets better than that.
The human body is warm blooded and not cold bolded.